4. Step 1 Elig: Central Nervous System Function - Patients may be enrolled in the study if they have an altered neurological status, such as somnolence, which is attributed to hydrocephalus and/or mass effect from the brain tumor by the treating physicians. However, after tumor resection and placement of the catheter into the fourth ventricle, the protocol will only be continued if the patient has adequate central nervous system function, defined as: patient is not severely somnolent or comatose and has adequate clinical performance status as defined in protocol section 3.2.2.1.